Portable tool



Nov. 25, 1941. E. B. LEAR PORTABLE TOOL Filed June 9, 1939 INVENTOR ML 8L542 ATTORNEY Patented Nov. 25, 1941 PORTABLE TOOL Earl B. Lear,Garfield Heights, Ohio, assignor to The Cleveland Pneumatic Tool CompanyCleveland, Ohio, a corporation of Ohio Application June 9, 1939, SerialNo. 278,213

6 Claims.

This invention relates broadly to fluid actuated portable tools, butmore particularly to portable tools especially fitted for setting orremoving bolts, nuts or the like.

One object of this invention is to produce a fluid actuatedreciprocatory motor with means for automatically transforming thereciprocatory motion of the motor into rotary motion capable of beingtransmitted to the work in either directlon.

Another object of this invention is to produce a simple and eflicientpower wrench through which reciprocatory motion of a power actuatedelement may be transformed into an intermit tent rotary motion of adriven member, the wrench including means for selectively controllingthe direction of rotation of the driven member.

Another object of this invention is to produce such a portable toolforming a compact and slender assembly, which can be handled andoperated without diificulty.

Other objects and advantages more or less ancillary to the foregoingreside in the specific construction and aggroupment of the elementspeculiar to this structure, as will become apparent from a more completeexamination of this specification.

In the drawing:

Fig. 1 is a longitudinal sectional view of a tool embodying theinvention.

Fig. 2 is a fragmentai view of the upper end portion of the tool shownin Fig. 1, with the movable parts in another position.

Fig. 3 is an enlarged cross sectional view taken in a plane indicated byline 3-3 in Fig. 1.

Fig. 4 is an enlarged cross sectional view taken in a plane indicated byline 4-4 in Fig. 1.

Fig. 5 is an enlarged cross sectional view taken in a plane indicated byline 5-5 in Fig. 1.

Fig. 6 is an enlarged cross sectional view taken in a plane indicated byline 6-6 in Fig. 1.

Referring to the drawing, l represents a cylinder formed with a pistonchamber The upper end of this chamber is closed by a cap I! clamped onthe cylinder by a handle l3 which is rigidly secured to the cylinder byany suitable means. The handle |3 extends partway over the upper end ofthe cylinder In, which is reduced to form a sleevelike portion l4 spacedfrom the interior of the handle l3 to provide a valve chamber withinwhich is reciprocably mounted a valve I6 adapted to seat on an annularshoulder formed on the cylinder l0, and on the opposed end ll! of thecap l2. The valve 14 is nothing more than the usual ring valve subjectedto pressure conditions within the chamber l5 for automatically engagingeither the seat H or l3, thereby controlling the admission of the motivefluid into the piston chamber H as hereinafter explained.

To the handle I3 is also secured a connection 20 through which motivefluid may be admitted into a port 2| by depressing a throttle trigger22. The port 2| opens into the valve chamber l5 from which leads aplurality of ports 23 located through the valve seat I8 and opening intothe upper end of the piston chamber I I through an annular groove 24 andradial ports 25. Leading from the valve chamber l5 through the valveseat ii, there is one or more ports 26 opening into the front end of thepiston chamber through a radial. port 21, while the chamber II isprovided with an upper exhaust port 28 and a lower one 29.

Near its front end, the cylinder has an apertured partition 30 extendingthereacross and through which is slidably mounted the shank 3| of asplined stem or spindle 32, which shanks extends into the piston chamberII to receive impacts from a piston 33 reciprocably mounted therein.Below the partition 30, the cylinder I0 is again formed with a cushionchamber 34, which is closed by the sleeve portion 35 of a spacer 36, theformer extending into the chamber 34 while the latter abuts against thefront end of the cylinder In as clearly shown in Fig. 1. On the stem 32is formed an annular flange or collar 31 reciprocably mounted within thecushion chamber 34, which chamber has its lower end in constantcommunication with the port 26 through a radial port 38 and its upperend with the atmosphere through a vent 39.

Clamped against the spacer 36 by bolts 40, there is 'a front casing 4|disposed coaxially with the center axis of the cylinder Ill. As shown inFig. 1, the bolts extend through apertured lugs 42, 43 and 44 formed onthe cylinder In, the spacer 36 and the front housing 4| respectively.The adjacent end portions of the spacer '36 and front housing 4| areinternally machined, the former to accommodate a rotatable ratchet ring45 having teeth 46 formed on the peripheral wall thereof, while thelatter accommodates a similar ring 41 formed with teeth 48. These tworatchet rings are spaced by a third ring 49 having a handle 50 rigidlysecured thereto and extending laterally therefrom to the exterior of thefront casing 4| through a slot 5| cut through the side wall of thecasing. Adjacent the ratchet ring 45, the spacer 36 is adequatelymachined to pivotally accommodate one or more pawls 52 constantly urgedin engagement with one side of the teeth 46 by a spring pressed plunger53, while the front housing 4| adjacent the ratchet ring 41 is similarlymachined to pivotally receive the pawls 54 engage'able with the one sideof the teeth 48 and urged inwardly by spring pressed plungers 55. Asshown in Fig. 3, the pawls 52 are located in a manner preventingrotation oi the ring 45 in a clockwise direction, while in Fig. 5 thepawls 54 are located in a manner preventing rotation of the ring 41 in acounterclockwise direction. The pawls 52 and 54 are somewhat longer thanthe width of the rings 45 and 41. and consequently extend partway overthe ring 49, which has its peripheral wall adjacent the pawls 52provided with two diametrically opposed notches I5 and adjacent thepawls 54 with two similar notches I8. Internally, the ring 45 isprovidedwith left hand relical splines 58 engaged by complementalsplines 51 formed on the portion of the stem 32 extending through thering. The ratchet ring 41 is internally machined with helical right handsplines 58 engaged by similar splines 59 formed on the adjacent portionof the stem 32. Between the splines 51 and 59 of the stem 32, there isprovided an annular recess 50 of a width calculated to prevent possibleengagement of the spines 5! with the spline 58 of the ring 41 or of thesplines 59 with the splines 58 of the ring 45.

The stem 32 extends beyond the portion formed with the splines 59, whereit is slightly reduced in diameter and is provided with straight splines5| meshing with corresponding internal splines 82 formed within theupper end portion of a chuck 63 rotatably mounted within the fronthousing 4| .and held therein against endwise movement by a retaining nut84 engaging an annular flange 85 formed on the chuck and located withina counterbore 66 forming the lower end of the front housing 4|. beyondthe front end of the front housing 4| where it is made of a polygonalcross section as at 6'! to receive a socket 68 held thereon againstgravity by a spring pressed ball 69 carried by the chuck 64 andextending into detents 10 formed within the socket 68, which socket isadapted to engage the work such as a nut 1| threaded on the bolt 12 forclamping together two plates 13.

In the operation of the tool, when motive fluid is admitted into thevalve chamber 5 through the port 2|, if the valve I5 is positioned asshown in Fig. 1, the motive fluid will flow through the ports 23 intothe groove 24 and therefrom into the upper end of the piston chamberthrough the ports 25, thereby acting on the piston 33 for P driving itdownwardly. As the piston approaches the endof its working stroke, theatmospheric air stored within the front end of the piston chamber IIwill be compressed by the piston causing upward pressure to be exertedon the valve l6, which pressure will together with a drop of pressuretaking place within the upper end of the piston chamber II when thepiston uncovers the exhaust port 28, cause the shifting of the valvefrom the position shown in Fig. 1 to the position shown in Fig. 2. Afterthe piston 33 has delivered its impact on the shank 3|, it willimmediately be driven rearwardly by the action of the motive fluidadmitted into the front end of the piston chamber through the passage 26and port 21. As the piston reaches the upper end of its return stroke,the air compressed within the upper end of the piston chamber lltogether with a drop of pressure within the front end of that chamber bythe piston uncovering the exhaust port 29, will again cause the valve l3to shift from the position show in Fig. 2 to that in Fig. 1, thuscompleting the cycle.

From the above explanation, it will be understood that by depressing thetrigger of the throt- The chuck 83 extends tle valve 22. automaticreciprocation of the piston 33 is eifected for imparting a rapidsuccession of impacts to the shank 3| of the stem or spindle 32. It willalso be understood that any suitable type of reciprocatory motor may beincluded in the mechanism without in any way departing from the scope ofthe invention.

Referring now more particularly to the invention, it is again pointedout that the impacts of the piston on the shank 3| will causelongitudinal motion of the stem 32, which motion is limited by motivefluid being admitted into the cushion chamber 34 through the port 38concurrently with the admission of the motive fluid into the front endof the piston chamber [I through a port 21 for effecting the returnstroke of the piston. In, other words, after impacts of the piston 33 onthe shank 3| effecting the working strokes of the stem, the motive fluidwill automatically be admitted under the collar 31 of the stem 32 foreffecting return movement of the stem into the position shown in Fig. l,in which instance, the chamber back of the collar is vented to theatmosphere via the vent 39.

When the ring 49 is positioned as shown in Fig. 4, the notches 15 arelocated out of registration with the pawls 52, causing them to rest onthe peripheral wall of the ring 49 and consequently maintaining them outof engagement with the teeth 48 of the ratchet ring 45. In this positionof the ring 49, the notches 16 are located for registration with thepawls 54 enabling them to engage the teeth 48 of the ratchet ring 41 fornormally preventing rotation of the ring in a counterclockwise directionin Fig. 5. In this instance, during the working strokes of the stem 32,its splines 51 cooperating with the splines 56 of the ratchet ring 45are rendered ineffective due to the disengagement of the pawls 52 withthe teeth of the ring 45, while the stems splines 59 engaging thesplines 58 of the ratchet ring 41 will, during the working stroke of thestem 42, tend to rotate the ring 41 in a counterclockwise direction inFig. 5, which rotation is prevented due to the engagement of the pawls54 with the teeth. 48 of the ring, thus causing rotation in a clockwisedirection in Fig. 5 to be imparted to the stem 32, which rotation is inturn transmitted to the chuck 63 by the driving connection including thesplines 6| and 62 of the stem 32 and sleeve 62 respectively. From thechuck 83, rotation is finally transmitted to the socket 68 for rotatingthe work engaged thereby.

During the return stroke of the stem 32, the splines 59 cooperating withthe splines 58 of the ring 41 will now impart rotation to the ring in aclockwise direction in Fig. 5, while the pawls 54 simply ride over theteeth '48, thus enabling return stroke of the stem without impartingrotation thereto and consequently enabling the work 1| heretoforerotated in one direction to remain momentarily stationary. Subsequentlythe impact of the piston 33 on the shank 3|will again eil'ect theworking stroke of the stem 32 and its consequential rotation in aclockwise direction for again rotating the work.

When it is desired to rotate the work in the other direction, the ring49 may be rotated to bring its handle 50 to the other end of the slot5|, in which instance the notches I5 will be located for registrationwith the pawls 52 to enable the engagement of the pawls with the teeth46 of the ratchet ring 45, while the notches 16 will be moved out ofregistration with the pawls 54 resulting in the engagement of the pawls54 with the peripheral wall of the ring 49 to maintain the pawls out ofengagement with the teeth of the ring 41. In this last position of thering 49, during the working stroke of the plunger 32 resulting from theimpact of the piston 33 on the shank 3 I, the stem spline 51 cooperatingwith the spline 56 of the ratchet ring 45 will normally tend to rotatethe ring in a clockwise direction in Fig. 3, which rotation is preventedby the engagement of the pawls 52 with the teeth 46 of the ring, thusresulting in the rotation of the stem in a counterclockwise direction.In this instance, this rotation of the stem in a counterclockwisedirection is also transmitted to the socket 68 for rotating the nut IIto remove it from the bolt 12, that is, for rotating the work in adirection adverse to that previously referred to. During the returnstroke of the plunger 32, its spline 51 active on the spline 56 of theratchet ring 45 will rotate the ring in a clockwise direction in Fig. 3,which rotation will take place while the pawls 32 simply ride the teeth46 of the ring and the stem 32 is moved back into the position shown inFig. 1 without having any rotation imparted thereto.

From the foregoing explanation, it will be understood that impacts ofthe piston 33 on the stem 32 result in the rotation of the stem in oneor the other direction, which direction will be controlled by the simplerotation of the ring 49. Due to the impacts of the piston 33 on the stem32, the rotation thus transmitted to the stem and therefrom to thesocket 68 will be a sudden and powerful rotation found to be veryeifective for setting or removing the nut H or its equivalent. Becauseof the-rapid reciprocation of the piston 33 and consequently the rapidsuccession of impacts on the stem 32, the intermittent rotationtransmitted to the socket 68 actually takes the appearance of acontinuous rotation which is transmitted to the nut H by imparting tothe nut a vibratory action resulting from the reversal of the pistonstroke 33 and intermittent torque transmitted to the nut I I, whichvibratory action is known to be effective in setting or removing thework similar to the nut 1!.

Although theforegoing description is necessarily of a detailedcharacter, in order to completely set forth the invention, it is to beunderstood that the specific terminology is not intend ed to berestrictive or confining and it is to be further understood that variousrearrangements of parts and modifications of structural detail may beresorted to without departing from the scope or spirit of the inventionas herein claimed.

I claim:

1. In a tool of the character described, a housing, a rotatable spindlereciprocable within said housing, means including a pneumatic hammercoaxially with said spindle and active thereon for effecting itsreciprocation, two sets of longitudinally spaced oppositively disposedhelical splines on said spindle, a ratchet mechanism operativelyassociable with one or the other set of said splines for efiectingrotation of said spindle in one or the other direction by virtue of thestrokes of said spindle in one direction, and means for selectivelycontrolling the operative engagement of said mechanism with one or theother set of said splines.

2. In a tool of the character described, a housing, a work engagingchuck journaled within said housing, a reciprocable and rotatable stemconnected with said chuck against rotation relative thereto, two sets oflongitudinally spaced oppositively disposed helical splines on saidstem, a ratchet ring for each set of splines operatively associatedtherewith, pawls carried by said housing engageable with said ratchetrings for eiTecting rotation of said stem in one or the other directionby virtue of its strokes in one direction. rotatable means forselectively controlling the engagement of said pawls with said rings, apneumatic hammer connected with the housing and having a piston forimparting blows to said stem resulting in its strokes in said onedirection, and means on said stem subjected to the live air pressuresupplied to the hammer for effecting the strokes of said stem in theother direction.

3. In a tool of the character described. a housing, a work engagingchuck journaled within said housing, a reciprocable and rotatable stemconnected with said chuck against rotation relative thereto, two sets oflongitudinally spaced oppositively disposed helical splines on saidstem, a ratchet ring for each set of splines operatively associatedtherewith, pawls engageable with said ratchet rings for efiectingrotation of said stem in one or the other direction by virtue of itsworking strokes, rotatable means for se ectively controlling theengagement of said pawls with said rings, a pneumatic hammer connectedwith the housing and having a piston active on said stem for effectingthe working strokes thereof, a head on said stem, and means forsubjecting said head to live air pressure supplied to said hammer foreffecting the return strokes of said stem concurrently with the returnstrokes of said piston.

4. In a tool of the character described, a housing, a rotatable spindlereciprocable within said housing, means including a pneumatic hammercoaxially disposed with said spindle and active thereon for efiectingits reciprocation, two sets of oppositively disposed helical splines onsaid spindle one above the other, means operatively associated with saidsplines for effecting rotation of said spindle in one or the otherdirection by virtue of the stroke of said spindle in one direction, andmeans for selectively controlling the direction of rotation of saidspindle.

5. In a tool of the character described. a housing, a rotatable spindlereciprocable within said housing, including a pneumatic hammer coaxiallydisposed with said spindle and active thereon for effecting itsreciprocation, a rotation mechanism within said housing includinglongitudinally spaced means on said spindle responsive to its strokes inone direction for effecting its rotation in either direction, and meansoperatively associated with said mechanism for selectively controllingthe direction of rotation of said spindle.

6. In a tool of the character described, a housing, a rotatable spindlereciprocable within said housing, means including a pneumatic hammercoaxially disposed with said spindle and active thereon for efl'ectingits reciprocati0n two sets of longitudinally spaced oppositivelydisposed helical splines on said spindle, a ratchet ring for each set ofsplines operatively associated therewith, pawls engageable with saidratchet rings for effecting rotation of said spindle in one or the otherdirection by virtue of its strokes in one direction, and means forselectively controlling the engagement of said pawls with said rings.

EARL 1B.

